Skip to Content
Space

This is the most precise 3D map of the Milky Way ever made

Through data collected by ESA’s Gaia observatory, astronomers have just released a new 3D atlas of the galaxy and its stars moving through space
December 3, 2020
esa gaia
esa gaia
A still from an animation depicting the movements of the stars observed by Gaia.ESA

Data collected by the European Space Agency’s Gaia observatory has been used to create the most detailed 3D map of the galaxy ever made. The new data set could help scientists unravel many mysteries about the universe’s expansion and the solar system’s future.

What is Gaia? Launched in 2013, the Gaia observatory is intended to observe as many of the galaxy’s stars as possible. It is designed to measure stellar positions, distances, motions, and brightness with more precision than any instrument before, with the goal of cataloguing approximately 1 billion objects. It is designed to observe each object about 70 times or so in order to track their motions and velocities over time, accurate enough to measure the width of a hair from 2,000 kilometers away.

The new map: The latest data pinpoints the location and movements of just under 2 billion stars, with highly accurate measurements of about 300,000 stars within 326 light-years of the solar system. The new map shows us that our solar system’s orbit around the Milky Way is accelerating toward the center of the galaxy by seven millimeters per second. 

What could we learn? The point of the mission isn’t simply to get a glimpse of the galaxy’s stars in motion. The data could help astronomers answer a number of different scientific questions, including how the Milky Way was formed over time, where the solar system and other star systems are headed, what the expansion of the universe looks like, and the distribution of regular and dark matter throughout the galaxy. Previous Gaia data sets have been used to ascertain the mass of the Milky Way and how many sun-like stars might be orbited by Earth-light planets.

What’s next: Gaia will be operational until about 2022, but it’s holding up better than expected and could see its mission extend to 2024 or beyond. The final data release should catalogue more than 2 billion objects in the galaxy.

Deep Dive

Space

section of Rima Sharp captured by the LRO
section of Rima Sharp captured by the LRO

The moon didn’t die as early as we thought

Samples from China’s lunar lander could change everything we know about the moon’s volcanic record.

SpaceX Starship
SpaceX Starship

How SpaceX’s massive Starship rocket might unlock the solar system—and beyond

With the first orbital test launch of Starship on the horizon, scientists are dreaming about what it might make possible— from trips to Neptune to planetary defense.

Lucy launched on this Atlas V rocket from Cape Canaveral Space Force Station in Florida on October 16 and began its journey to Jupiter's Trojan asteroids, where the spacecraft will study how the solar system and its planets formed.
Lucy launched on this Atlas V rocket from Cape Canaveral Space Force Station in Florida on October 16 and began its journey to Jupiter's Trojan asteroids, where the spacecraft will study how the solar system and its planets formed.

This NASA spacecraft is on its way to Jupiter’s mysterious asteroid swarms

The spacecraft named Lucy is just starting its 12-year journey to see what asteroid clusters can teach us about the early solar system.

Thirty Meter Telescope Mirror concept
Thirty Meter Telescope Mirror concept

US astronomers want a giant telescope to hunt for new Earth-like planets

A newly published scientific wish list includes studies of habitable planets, black holes, and the origin of galaxies.

Stay connected

Illustration by Rose WongIllustration by Rose Wong

Get the latest updates from
MIT Technology Review

Discover special offers, top stories, upcoming events, and more.

Thank you for submitting your email!

Explore more newsletters

It looks like something went wrong.

We’re having trouble saving your preferences. Try refreshing this page and updating them one more time. If you continue to get this message, reach out to us at customer-service@technologyreview.com with a list of newsletters you’d like to receive.